Improvement in building-blocks



J. THOMPSON. 'Building Block.

No. 222,211. Patented Dec. 2.1879.

construction, with unusual security to the building from damage by the from the fluesz f "Ih'ehlocks may be made of any suitable material other than terracotta, and certain oflhem provided with holes for stove-pipes or earthen connections, if desired.

1 am aware that chimneys have been constructed of tubular blocks with additional tubes or passages, for the purpose of producjng a cooling circulation by up-and-(lown draft, is; in Patent No. 175,920, and also that chimeyshave been formed from. blocks having a f oufer' shell by planes at an angle with each theiy as in Patent No. 211,437.

fld i neither of thcsaid patents. One of utilized, as hereinhefore described filial tubular portion connected with, afn

o not wish, therefore, to be understood s claiming the distinguishing features em,

tli leading feat ures'of my inyentiou is, 'hov eyerdthat it is abuilding-block adaptedlto be Y -fi t,ted' -to others alongside pfiib, as. shcwuin g2, and that the channels or passages may B jmaking the iuteifiorflue rectangular in I i cross-section an; art n and parallel with tending round thecor rs,

points, viz: the max n ing the air in the'flue ax strength in the eutir b p 7 being'uuited with ,by firm conneqtioi What I claim- As 'an"'arti 

